Here is how to create excellent surround sound without fancy decoders or expensive equipment.
As they say "necessity is the mother of invention". Without the money for a proper setup (they (The Man) overcharge us (consumers) in Australia) my dad and I got his old speakers and amp and wired up something that sound like the real deal.
This instructable requires some (not much) knowledge about wiring speakers (plugs and whatnot)

Step 1: Equipment and Materials

Materials:
Amp (nothing fancy)
2 main speakers (pick these up cheap from garage sales/ flea markets or family)
2 car speakers (I used a $20 set)
Speaker cabling
Speaker mounting for main speakers (optional)

Tools:
Drill / screwdriver
Saw (regular or plasterboard type)
Pliers

Step 2: Arrangements and Connections

Arrange the speakers as in the diagram. Then use your wire to arrange the positive and negative connections as shown in the diagram. As I said this requires previous knowledge of speakers.

Step 3: Mount!

After you have hooked everything up you have to decide if you want to mount the speakers. I put the car speakers in the roof and the main ones on the wall. If you can't decide there are plenty of 'ibles on the subject, look around.